Drug delivery is a method or process of delivering a therapeutic agent or drug to achieve a therapeutic effect in an animal body. Certain drug delivery technologies employ iontophoresis to transdermally administer a therapeutic agent by using an electrotransport current to drive the therapeutic agent into the animal body. In a typical iontophoretic drug delivery device, a reservoir holding a therapeutic agent in a conductive medium is placed in contact with one of an anode or a cathode, and a reservoir holding a conductive salt solution is placed in contact with the other of the anode or the cathode. The reservoirs are typically placed in contact with the animal body and in contact with the corresponding electrodes, thus allowing a voltage difference established between the electrodes to drive an electrotransport current through the reservoirs into the animal body, thereby directly administering the therapeutic agent to the animal body.